Athearn RTR DCC Quick-Plug Equipped

[gcarter1945]

I purchased an Athearn GP-35 RTR DCC Quick-Plug Equipped with the idea of giving a clinic at our next Division event showing how easy it is to plug in the LM-3S and get your loco running.  I thought this would be an easy, no-brainer exercise because I have swapped out DCC decoders in other locomotives in my fleet, no problems.

It was easy enough to remove the DCC jumper board and plug in the LM-3S.  However, when I put the loco on the track it caused an immediate short circuit and shut down the Power Supply.  I ended up removing the Athearn circuit board and hard wired the WH-9 and plugging in the LM-3S.  So much for being able to show this easy process in my clinic.

Thinking that I possibly got a bad unit the first time, I was able to pick up another Athearn GP-40X RTR DCC Quick-Plug Equipped loco at our last Train Show.  Lo and behold, but I experienced the same exact problem with this unit when trying to plug in the LM-3S... instant short circuit.

I don't have any of my fleet that I can use to show this because the ones that are still DCC have proprietary decoders or have already been hardwired, and I am not going to buy another locomotive.

So, my friends, what is going wrong, what have I failed to do, and is there a fix?

Thanks for your time and consideration.

Geoff
Too soon old, too late smart

[KPack]

That's odd.  It's definitely not the LM-3S, that's for sure.  If anything it is something in the Athearn board, but what I'm not sure.  Could possibly be that someone previously wired the track wires wrong to the board. 

I've never bothered plugging a LM into an Athearn board....I always just remove it.  But I have plugged LM's into MTH, Atlas, and Kato boards without any issues whatsoever. 

-Kevin

[nodcc4me]

Did you happen to use the same 9-to-8 pin harness on both locomotives? If so, maybe that harness is bad.

[KPack]

Did you happen to use the same 9-to-8 pin harness on both locomotives? If so, maybe that harness is bad.

The Athearn RTR locos usually have a short 9 pin plug hardwired into the board, so a separate harness shouldn't be needed.

[gcarter1945]

The GP-35 was brand new still sealed package.  The GP-40X had been out of the box and test run.  I doubt that either factory board had been messed with.  They both ran as expected on straight DC before I tried messing with the decoder.

Maybe I'll try one of my remaining DCC locos that use the 9-pin plug vs. some proprietary board.

Thanks for your inputs.

[Nick]

This is odd. I currently have three Athearn RTR Quick-Plug Equipped with LM-3S. The install was a breeze. I plugged in the module with the hardwired harness and it worked perfectly. I have no idea of what could be causing the issue, but it is definitely not the LM-3S.

-Nick

[William Brillinger]

It sounds like a bad harness to me.

If you have a multimeter, check the disconnected harness for shorts.

[gcarter1945]

I got a hold of a Digitrax DH126D for a few bucks and plugged that in to the Athearn Quick Plug DCC and everything worked as advertised.  Given this partial success, I would say the Quick Plug is not faulty.  There seems to be some incompatibility between the Quick Plug and RailPro.  Perhaps there is something on the Quick Plug that needs to be disconnected/removed to let the RailPro be compatible.  Any thoughts?

Thanks for your time and efforts.

Geoff

[PerezBill]

I would recommend finding the pinouts for plug on the athearn board then look at the pinouts for the railpro. They wiring may be different. I believe I recently read about an issue like this (on this forum?) in the recent past. The answer was to hard wire the railpro in the engine and don't use the quick plug.

Bill

[Alan]

Is it possible you accidentally defeated the plug indexing (pin offset) and inserted the LM3 upside down?

[BruceRogers]

I have several Athearn Ready to Roll engines that I just stuck in the LM module into the 9 pin plug. It's not my first choice as I prefer hard wiring in the 9 pin JST harness. So far I've had no problems with them. I'd mail the locomotive with the module in back to Ring and see if they can figure it out. You never know there could be glitch somewhere in the system we don't know about.  I recently had to do this with an HC-2. Tim fixed it and made a change to the software so others won't have the problem.

[gcarter1945]

PerezBill,

Thanks, I ended up doing exactly what you suggested.  However, that defeated my purpose to show how easy it is to install RailPro in a "DCC Ready" loco.

Alan,

No, I installed RailPro with the correct orientation. Thanks for the suggestion though.

BruceRogers,

Thanks for the input.  Unfortunately I am out of time as I'm giving the clinic in two days.  Perhaps I'll take your suggestion next week, after the clinic.

To all the rest of you who responded... Thanks for your time and suggestions.

Geoff

[TwinStar]

What was the verdict on this?

[gcarter1945]

The final verdict was that I had a defective LM-3S.  Sent it back to Ring Engineering and they replaced it. I like their customer service very much.

Thanks to all you folks here who gave suggestions and your time to help.

Geoff

[TwinStar]

The final verdict was that I had a defective LM-3S.  Sent it back to Ring Engineering and they replaced it. I like their customer service very much.

Thanks to all you folks here who gave suggestions and your time to help.

Geoff

Glad to hear you got it worked out.